Dispensing of high-viscosity liquids

ABSTRACT

A body of liquid to be dispensed is admitted into a receptacle under atmospheric pressure, so that a free space at atmospheric pressure remains above the level of the liquid in the receptacle. Thereafter, the atmospheric pressure is changed to subatmospheric pressure in the free space, either before or in response to dispensing of liquid from the receptacle; the dispensed liquid is replaced with a compensatory quantity of air which is admitted below the level of the liquid in the receptacle in such a manner that gas bubbles will rise through the viscous liquid to the free space, to become enriched with moisture from the liquid so that the atmosphere in the free space will always be at a degree of humidity sufficient to prevent the occurrence of surface drying of the liquid.

United States Patent [191 Kuckens [54] DISPENSING or HIGH-VISCOSITY LIQUIDS [75] Inventor: Aleander Kuckens, Hamburg,

Germany [73] Assignee: Dagma Deutsche Automaten und Getraenkema GmbH, Hamburg, Germany 22 Filed: Apr. 13, 1972 21 Appl. No.: 243,789

Rama us. Application. Data [63] Continuation-impart of Ser. No. 204,693, Feb. 29,

19.72, abandoned.

[30] Foreign Application Priority Data Dec. 5, 1970 Germany 2059925 [52] US. Cl. 222/481, 222/510 [51] Int. Cl .Q. B67d 3/00 [58] Field of Search 222/510, 518, 542, 548, 222/559, 504, 481, 481.5, 482, 1, 185, 181,

[56] References Cited UNITED STATES PATENTS 493,877 3/1893 Schulueter 222/188 227,697 5/1880 Massey 222/188 2,959,328 11/1960 Palmer 222/510 X 5] Apr. 30, 1974 3,638,831 Pauwels et al 222/1 2,564,427 8/1951 DeRu geris 222/510 X 3,054,533 9/1962 Kurek 222/504 X 3,133,677 5/1964 Bertels..- 222/510 X 3,401,850 9/1968 Anderson... 222/518 X 2,319,517 5/1943 Rand 222/510 X 2,912,145 1 1/1959 Amen 6t 31. 222/481 Primary Examiner,Stanley H. Tollberg Assistant Examiner-FrancisJ. Bartuska Attorney, Agent, or Firm-Michael S. Striker 57 ABSTRACT A body of liquid to be dispensed is admitted into a receptacle under atmospheric pressure, so that a free I space at atmospheric pressure remains above the level of the liquid in the receptacle. Thereafter, the atmospheric pressure is changed to sub-atmospheric pressure in the free space, either before or in response to dispensing of liquid from the receptacle; the dispensed liquid is replaced with a compensatory quantity of air which is admitted below the, level of the liquid in the receptacle in such a manner that gas bubbles will rise through the viscous liquid to the free space, to become enriched with moisture from the liquid so that the atmosphere in the free space will always be at a degree of humidity sufficient to prevent the occurrence of surface drying of the liquid.

19 Claims, 7 Drawing Figures PATENTEDAPNO 1914 3807607 SHEEI 2 U? 4 HIM-HIM mm :m

WWW]! 11L IIHHJIMI IIIIIHII'HIIHIH 1m PATENTED APR 3 0 1974 33307507 SHEET 3 OF 4 PATENTEDmau 1914 3.807507 sew g m 4 n I I I I I I I II I I I II I DISPENSING OF HIGH-VISCOSITY LIQUIDS C ROSS-REFERENCE TO RELATED APPLICATION The present application is a continuation-in-part of my application, Ser. No. 204,693, filed on Feb.'29, 1972, now abandoned, in my name under the title Method of Preventing Waste and Drying up of Syrups and Similar Fluid concentrates in Storage Tanks Provided with Dispensing Devices.

BACKGROUND OF THE INVENTION The present invention relates to the dispensing of high-viscosity liquids, and more particularly to methods of dispensing such liquids and to apparatus for effecting such dispensing.

In the dispensing of high-viscosity liquids, such as syrups or other liquids of high sugar content, various problems are encountered. The net result of these problems is that it is very difficult and requires special efforts to keep the receptacles, from which such liquids are to be dispensed, in clean condition and functional.

When such a liquid is dispensed from a receptacle of the dispenser, the level of liquid recedes more or less slowly, so that some of the liquid may dry up on the inner surface of the receptacle wall and also in the dispensing mechanism itself, requiring laborious and timeconsuming cleaning operations. When the body of liquid accommodated in the receptacle has finally been completely dispensed it is found that a thin tacky film of liquid has become deposited on those portions of the receptacle on which otherwise no encrustations appear, and this is particularly disadvantageous for hygienic reasons because bacteria and various contaminants tend to settle in such film deposits.

It has been proposed and is general practice to dispense from dispensing apparatus only syrups and/or concentrates having a relatively low sugar content, for instance on the order of about 50 on the Brix scale, (hereafter called Brix for short), in the hope to thereby reduce the occurrence of encrustations to a minimum. This does have to some extent the desired effect, but has the disadvantage that such low sugarcontent liquids do not have a self-preserving characteristic as can be obtained by employing syrups and concentrates having a high sugar content.

If, on the other hand, such high-sugar-content liquids are utilized, the problems relating to the formation of encrustations and to cleaning will inevitably occur and in most instances it is not possible to perform the necessary cleaning operations in situ. It is therefore usually necessary to remove the receptacle of the dispenser and to carry it to a suitable location where it is to be cleaned. On the other hand, if such cleaning is not performed immediately after the liquid contents of the receptacle have been dispensed, similar hygienic problems as with liquids of low sugar concentration will arise here also.

Insofar as the prior-art dispensing devices for high viscosity liquids are concerned, it is known to control the valve body, which in turn controls the dispensing opening of the device, by means of an electromagnet. In such construction the valve body which is to be moved between open and closed positions is of a magnetizable material and the electromagnet is energized when the valve body is to be moved from its closed to .its open position, with the valve body being allowed to return under the influence of gravity to its closed position upon termination of the energization of the electromagnet.

The valve body is customarily located in and surrounded by the liquid being dispensed. The coil of the electromagnet which is energized to lift the valve body off its valve seat must also be located in close proximity to the-valve body and therefore to the liquid to be dispensed, as a result of which over a prolonged period of operation, the heating effect which takes place in the coil of the electromagnet will result in the transmission of heat into the viscous liquid being dispensed. This changes the viscosity of the liquid, leading to improper dosing, that is to the dispensing of inaccuratequantities of liquid. I

V A further disadvantage of the prior-art dispensing devices resides in the simple fact that if the liquid is highly viscous, inaccuracies in dispensing result from the flow of the liquid about the magnetizable valve body when the same has been moved to open position and the liquid flows about it and into the dispensing opening.

Another disadvantageof the constructions according to the prior art resides in the fact that frequently the valve body, when it has been moved to open position, is pressed against a wall portion of the receptacle provided with the valve. If the liquid to be dispensed is highly viscous, particularly if it has a high sugar content, a suction effect occurs which can be so strong that even if the valve body is biased to closed position by a spring rather than being permitted to move to closed position under the influence of gravity it may not be separated from the wall quickly enough when the energization'of the electromagnetic coil is terminated; this can result in a retardation of the return of the valve body to closed position, and in turn will have the effect that the quantity of liquid being dispensed is inaccurate and never precisely reproducible from one dispensing incident to the next.

This latter difficulty has been proposed to be overcome by utilizing not only a spring biasing the valve body to closed position, but utilizing a spring which is strong enough to overcome the aforementioned suction effect. However, aside from the fact that the expenses for construction of the device particularly if it is a small device become uneconomically high under such circumstances, it has been observed that the necessarily increased size of the magnetic coil which of course must be stronger than before because it has to overcome the stronger action of the larger dimensioned spring will necessarily heat up more and will then cause more substantial heating of the viscous liquid, thereby resulting in a more pronounced change in the viscosity of the liquid.

SUMMARY OF THE INVENTION It is, accordingly, a general object of the invention to overcome the disadvantages of the prior art.

More particularly, it is an object of the present invention toprovide an improved method of dispensing high- 3 liquids, particularly liquids of high sugar content. This method comprises the steps of admitting into a receptacle under atmospheric pressure a body of liquid to be dispensed so that a free space at atmospheric pressure remains above the level of the liquid in the receptacle. Thereupon, the entry into the free space is effected during dispensing of liquid from the receptacle of a quantity of gaseous fluid which compensates for the dispensed liquid in form of gaseous bubbles of sufficient size to rise through the body of liquid to the level but to have sufficient dwell time within the body to become moisture-enriched by the liquid. In this manner, the atmosphere accommodated in the free space is maintained at a sufficient degree of humidity to prevent the occurrence of surface drying of the liquid at and above the level, for instance on the inner surface bounding the free space.

An apparatus according to one feature of the invention comprises a receptacle having an upper portion and a lower portion, and being adapted to accommodate a'body of liquid to be dispensed. Outlet means is provided in the lower portion for discharge of liquid to be dispensed, and valve means controls discharge of liquid through the outlet means and includes a valve body movable downwardly to a sealing position and upwardly to a dispensing position. Control rod means is connected with the valve body and extends upwardly into the receptacle through the body of liquid, including an upper end portion located above the upper level of liquid. Electromagnetic means is provided for shifting the control rod means longitudinally of itself for thereby effecting movement of the valve body to its dispensing position. This electromagnetic means cornprises an armature carried by the end portion of the control rod means, and a normally deenergized stationary coil surrounding the armature and being energizable for lifting the armature and thereby shifting the control rod means to effect-movement of the valve body to its dispensing position.

The present invention overcomes the disadvantages of the prior art. in particular, the manner in which the apparatus according to the present invention is constructed assures that the coil of the electromagnetic means located above and away from the upper level of the liquid usually outside the receptacle cannot transmit heat to the liquid to be dispensed and thus cannot change the viscosity of this liquid. This in itself improves the accuracy of the'quantities of liquid which are dispensed, aside from the fact that the magnetizable armature attracted by the energized coil is now also no longer located within the body of liquid to be dispensed and remains clean at all times, an advantage which is supplemented by the fact that the weight of the plunger constituted by the armature, the control rod means and the valve body can be chosen sufficiently high to make it unnecessary to provide a biasing spring to return the valve body to closed position.

The frequently necessary cleaning of the receptacle which is known from the prior art constructions, is avoided by the present invention in that it becomes possible according to a further concept to continually refill the receptacle with additional liquid to be dispensed without having to fear either that the contents of the receptacle may become spoiled or that any of the liquid will be subjected to surface drying and formation of encrustations. For this purpose the control rod means is surrounded by a pipe or tube which extends within the rceptacle, having a lower open end which opens beneath the level of liquid to be dispensed and having an upper openend which extends outwardly of the upper end of the receptacle and is surrounded by the coil of the electromagnet. According to a currently preferred embodiment, the upper open end is associated with a vent valve which preferably will open au tomatically in response to the development of subatmospheric pressure in the pipe; The reason for this construction will now be set forth as follows:

Liquids having for instance a 6070 Brix value are very highly viscous, and'small air bubbles can become completely entrapped and prevented from passing through such liquids. It is therefore necessary that if air bubbles are to rise through such a body of liquid, they must be sufficiently buoyant to assure that they can overcome the high viscosity of the liquid and can rise to the upper level of the liquid, even though the speed of the rise of such bubbles is strongly retarded. The present invention makes use in particular of the retardation effect on these gas bubbles, employing them to become enriched during their passage through the liquid with moisture, which enrichment of course is facilitated by the fact that they are retarded and have a relatively long dwell time in the body of liquid, and to yield up their moisture to the atmosphere which is located above the upper level of the liquid in the receptacle, It

is known that a low moisture content in the atmosphere mosphere above the upper level of the liquid in the receptacle relatively high due to the frequent importation of additional moisture by the gas bubbles. This, however, requires of course that the space in the container above the upper level of the liquid-is air-tightly sealed with respect to the ambient surroundings.

Strongly viscous liquids having a high sugar content tend to significantly change in their viscosity in dependence'upon the ambient temperature. For this reason it is known already to cool such liquids, especially when automatic dispensing of the liquid takes place, in order to assure the viscosity to be constant, a consideration which is necessary to obtain precisely calculated dispensed quantities. However, cooling as a rule involves a reduction in the humidity of the air located in the receptacle above the upper level of the liquid, so that high-viscosity sugar-content liquids, which in any case tend to drying and the formation of encrustations, are encouraged to .do so under such circumstances. The present invention, however, avoids this by assuring that to all intents and purposes only such gas or air can reach the sealed space above the upper level of the liquid in the receptacle, which has already become enriched with humidity during the travel through the body of liquid to be dispensed.

When liquid of the type here under discussion is for instance to be dispensed automatically, then the receptacle must be vented if the liquid is accommodated in a receptacle which is closed with respect to the atmosphere. in other words, air must be permitted to enter as the liquid is dispensed. The invention makes use of this by assuring that the incoming air will enter in the region of the bottom of the receptacle and certainly downwardly spaced from the upper level of the liquid therein so that'the incoming air will rise in form of air bubbles so slowly through the viscous liquid to the upper level thereof that the air bubbles can become enriched to a certain extent with moisture from the liquid, which moisture they subsequently can yield to the atmosphere in the sealed space above the upper level of the liquid to prevent the atmosphere from becoming dry enough to encourage surface drying of the liquid.

Since a certain amount of chilling will take place at the walls of the receptacle, particularly in those areas which are not in contact with liquid in the receptacle, a certain small condensation effect will take place at the inner side of the receptacle. wall, so that the drying of the air above the upper level of the liquid in the receptacle is thereby further discouraged.

All of this means that it is now no longer necessary to clean the receptacle before it can be refilled, and this is aided by the fact that all movable components of the apparatus which are in contact with the liquid will always be covered by the viscous liquid itself. If the newly-added replenishing liquid is to have the same viscosity as the liquid already in the receptacle, taking into consideration that even small temperature differences may result in a change in the viscosity conditions, then the level of liquid in thereceptacle should be so high that a renewed dispensing of liquid will take place from the residual amount of previously contained liquid in the receptacle, whereas the newly added replenishing liquid will still be far enough above the outlet so as not to be drawn in and dispensed until the newly added liquid has assumed the same temperature as the liquid previously contained in the receptacle. It may be necessary, if the receptacle is accommodated in a refrigerated space, for instance a space which has a temperature lower than 5C., that the replenishing liquid itself be cooled before it is admitted into the receptacle. Small differences in the temperatures of the liquid in the receptacle and the replenishing liquid can and may occur, and will not be disadvantageous when they occur in the apparatus according to the present invention, so that as tests have shown it is actually possible to dispense liquid from suchan apparatus for months on end without having to clean the apparatus inbetween. This of course requires that the receptacle be air-tightly sealed, that is that the apparatus be provided with an arrangement which permits the entry of air in compensation for a dispensed amount of liquid but which will upon termination of the dispensing incident again air-tightly seal the receptacle.

The dimensions of the incoming air bubbles can be predetermined by appropriately dimensioning the diameter of the pipe mentioned earlier and/or by inclining the pipe from the vertical, so that the incoming air bubbles will be sufficiently large to have an amount of bouyancy permitting them to properly rise through the highly viscous liquid to the upper level thereof, whereas on the other hand they will rise slowly enough so as to have a sufficient dewll time to be enriched with moisture from the liquid even if the air is dry, for instance, has been cooled before it enters in form of air bubbles.

A further consideration which has been taken into account in the present invention is the fact that gas at sub-atmospheric pressure will accept less humidity than for instance air at normal atmospheric pressure. This circumstance is utilized by the present invention to reduce the amount of moisture which must be supplied in order to keep the atmosphere in the sealed container above the upper level of the liquid therein sufficiently humid to prevent surface drying of the liquid. In particular, the atmosphere in the sealed space above the upper level of liquid in the receptacle may be changed from atmospheric to sub-atmospheric pressure after the liquid has been admitted into the receptacle and before dispensing-takes place, or according to another concept of theinvention it may change from atmospheric to subatmospheric pressure in automatic response to the dispensing of liquid. The latter is achieved in that, when the opening for the dispensing of the liquid "is unblocked, the vent tube is automatically closed with respect to the ambient atmosphere. This means that when liquid is introduced into a receptacle so constructed it will rise in the receptacle but not in the vent tube which is automatically closed. When the inlet opening of the receptacle is hermetically closed afterthe receptacle has beenfilled and the device is ready for dispensing the'liquid, the vent tube is automatically opened with respect to the atmosphere. The liquid contained in the receptacle irrespective of its particular viscosity and the relatively high specific weight which depends uponthe given sugar or dry substance content will now attempt to enter into the vent tube according to the principle of communicating vessels. Because of this the liquid will automatically and necessarily cause the development-of sub-atmospheric pressure above its upper level'in the receptacle and this sub-atmospheric pressure, will remain in existence. When during dispensing of liquid, air bubbles enter into the receptacle under normal atmospheric pressure and prevented because the atmosphere above the level of liquid in the receptacle will always humid to prevent such drying.

' The valve body for opening and closing the dispensing opening is advantageously, although not necessarily, of a non-magnetizable material and may be configurated in various different ways, for. instance, it may be ball-shaped, conical or the like, so that only 7 a line contact takes 'place'with its valve seat when it is in closed position, whereas when it is in open position only a point contact can take place with a wall of the receptacle with which the valve body may come in contact when in open position. This avoids the disadvantages which have been outlined above, and which result in the aforementioned suction effect.

It is even more advantageous, however, if the vent tube through which'air is admitted during dispensing of liquid, is providedzin the region of its lower end with a guide for the rod carrying the valve member, with the guide being such that when the valve member is in its open position it cannot contact the wall of the receptacle at all. Such a guide may be in form of a disc or the like, having a hole or a slot through which the rod extends. The valve body itself may be turnably mounted at the lower end of the rod so that even when it contacts the wall of the receptacle, it will roll along the same'and possible friction with respect to the wall will be very low as a result of this.

If a vent valve is provided as outlined earlier, its control can be effected with a control arm with which the be sufficiently vent valve can be moved to open position, and advantageously the control arm will automatically -move the vent valve to open position after the filling of the receptacle has been carried out. According to an advantageous embodiment the control arm may be a part of or provided on the cover of a housing which accommodates the receptacle and which cover must be moved to open position to expose the inlet opening through which liquid is introduced into the receptacle, and is moved to close position after the liquid has been so introduced.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a somewhat diagrammatic vertical section illustrating one embodiment of the invention with the valve member in closed position and with the receptacle filled with liquid;

FIG. 2 is a view similar to FIG. 1 showing the valve member in open dispensing position and with the level of liquid reduced due to dispensing;

FIG. 3 is a fragmentary detail view on an enlarged scale, showing a further embodiment of a valve member;

FIG. 4 is a view similar to FIG. 1 illustrating an embodiment using a vent valve and a control arm therefor;

FIG. 5 is a fragmentary detail view, on an enlarged scale, illustrating a closure for the inlet opening of the receptacle in FIG. 4;

FIG. 6 is a view similar to FIG. 4 illustrating the apparatus after filling with liquid and with the vent valve perated by the control arm; and

FIG. 7 is a view similar toFIG. 6 but showing the apparatus with some of the liquid dispensed and with the valve member in open position.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Discussing the drawing now in detail, and firstly the embodiments illustrated in FIGS. 1 and 2, it will be seen that reference numeral 1 identifiesa receptacle which is to contain a highly viscous liquid 2, for instance a high sugar-content syrup or concentrate or the like, having at least 60 Brix value. Reference numeral 3 identifies an outlet of the receptacle 1 through which liquid is to be dispensed from the latter and a portion 4 of the receptacle 1 converges in frustoconical manner to the outlet 3. Reference numeral 5 identifies an inlet opening in the upper end of the receptacle 1 through which liquid to be dispensed is admitted, and reference numeral 6 is a closure device by means of which the inlet opening 5 can be gas-tightly closed.

FIGS. 1 and 2 show that .a valve member 7 is provided which can sealingly close the outlet 3 as in FIG. I, or can be retracted to dispensing position as in FIG. 2. In the illustrated embodiment the valve member 3 is of ball-shaped configuration and is mounted in a bifurcated end portion of an upright control rod 8, being mounted by means of a pivot pin 7a so that it can turn about this pin. A reference to FIGS. 4 4 7 will, however, show that the valve member 7 can also be fixedly mounted on the control rod 8, that is not by means of the pivot pin 7a.

As the drawing shows, the control rod 8 extends upwardly in the receptacle, through the body of liquid 2 therein and carries atits upper end located above the upper level 14a of the liquid partly or completely outside of the receptacle 1 an armature 9, for instance of steel or other magnetizable material, which can be lifted in upward direction by the diagrammatically illustrated electrically-energizable coil 10. When this takes place, the armature 9 is raised and with it will be raised the rod 8, and the valve member 7, so taht the latter moves to the position shown in FIG. 2, opening the outlet 3 for dispensing of liquid. Depending upon the period of time for which the coil remains energized, a predetermined amount of liquid 2 can be dispensed through the outlet 3.

Due to the location of the coil 10 upwardly and outside of the receptacle 1 any heat developed during its operation will not be transmitted to the liquid 2 and cannot affect the viscosity of the same.

In the embodiment of FIGS 1 and 2 the control rod 8 is surrounded by an upright partition or vent tube 11 which extends from the outside of the upper end of the receptacle 1 through the latter towards the region of the bottom wall thereof and partitions the surface of the liquid 2 contained in the receptacle 1 into two portions,'the portion outside the vent tube 11 being at a higher level than that inside the same. The upper and lower ends of the vent tube 11 are open and in the region of the lower end there is provided a guide plate 13 having a slot 13a therein in which the rod 8 is guided. This means that the rod 8 has a certain amount of freedom in direction radially of the vent tube 11 and the valve member 7 can contact the wall of the receptacle portion 4 when the coil 10 is energized, as indicated in FIG. 2. The liquid level 14 corresponds to the static pressurepoint determined by the location of the lower edge of the vent tube 11.

The upper end of the vent tube 11 is provided with a vent valve 12 which is of a construction known per se such that it will admit communication of the interior of the vent tube 11 with the ambient atmosphere, and will thus permit entry of air into the interior of the vent tube 11, only when sub-atmospheric pressure prevails in the vent tube 11. If a higher pressure exists in the vent tube 1.1 then the'vent valve 12 willclose and prevent communication of the interior of the tube 11 with the ambient atmosphere. Thus, when the closure 6 is removed so that liquid can be introduced into the receptacle 1, it is impossible for any significant amount of the-liquid to enter the vent tube 11 because air cannot escape from the latter. This means that the liquid can rise in the vent tube 1 1 only to a small extent above the lower open end of the vent tube 11 when liquid is filled into the receptacle 1.

If, however, liquid is subsequently dispensed through the outlet 3 as shown in FIG. 2, then the liquid level will drop within the vent tube 11 to the lower edge of the same and at the same time a sub-atmospheric pressure will develop in the upper space In of the receptacle, that is above the upper level 14a of liquid 2 therein. This space then receives air which enters through the vent tube 11 and rises inform of air bubbles 20 (see FIG. 2) through the body of liquid 2, the valve 12 of course opening automatically, when as a result of the dispensing of liquid, a subatmospheric pressure develops in the vent tube 11 also.

The volume of liquid which is dispensed at any one time out of the outlet 3 is controlled exclusively by the length of time for which the coil remains energized, so that only the period of time for which the coil 10 is energized and the valve member 7 is in the position shown in FIG. 2 determines the amount of dispensed volume, because the static pressure point is above the lower edge of the vent tube 11 and sub-atmospheric pressure exists in the vent tube 11 and the space la; this means that during a given period of time only as much liquid can leave through the outlet 3 as gas enters during the same period of time to compensate for the dispensed liquid.

FIG. 3 shows that the valve member need not be ballshaped or spherical as in FIGS. 1 and 2 and again in FIGS. 4 7 but can also be of a different configuration.

Like reference numerals in FIG. 3 identify like elements as in FIGS. 1 and 2, except that the valve member is here identified with reference numeral 7 and is of essentially rhombic outline. Of course, it could also be simply conical or frustoconical and it will be noted that the valve member 7' is rigidly connected with the rod 8, rather than turnably via pivot pin 7a as in FIGS. 1 and .2.

Coming, finally, to the embodiment illustrated in FIGS. 4 7, it will be seen that here again like reference numerals have been used to designate the same components as previously. This embodiment differs in certain respects from that of FIGS. 1 and 2, particularly in the vent valve and in the manner in which the operation thereof is controlled.

As the drawing shows, the vent valve associated with the upper end of the vent tube 11 is identified in this embodiment with reference numeral 40, and has a valve plate 41 which is mounted on a plunger 42, the latter extending upwardly beyond the coil 10. The receptacle 1 is mounted or otherwise accommodated in a housing 43 which is only fragmentarily illustrated and which has a lid 44.

The receptacle 1 again has an inlet opening 5 as before, and this inlet opening can be opened and closed by appropriate manipulation of a closure device 45, which is shown in detail in FIG. 5. To gain access to the opening 5 and the device 45 it is necessary to raise the normally closed lid 44, that is to move it from the position shown for instance in FIG. 6 to the position shown in FIG. 4. Now the device 45 is exposed and can be removed. As FIG. 5 shows the device 45 has a circumferential surface which is surrounded by an annulus 46 of elastomeric material, and a toggle lever 47 is provided which, when moved to the position shown in FIG. 6,

will deflect the annulus 46 radially outwardly into en gagement with the wall surfaces surrounding the inlet opening 5, to thereby obtain a sealing effect. When the lever 47 is in the position of FIG. 5, however, the device can be lifted out of the inlet opening 5, as shown by the juxtaposition of FIGS. 4 and 5.

If, with the device 45 removed, liquid is admitted into the receptacle 1, then it will rise to a small extent in the lower end of the vent tube 11, as illustrated in FIG 4, causing the vent valve 40 to close and thereby prevent contact of the interior of the vent tube 11 with the ambient atmosphere.

Now the cover or lid 44 is moved to closure position in which it closes the housing 43 and conceals the receptacle 1. When it is so moved and assumes the position illustrated in FIG. 6, the cover or lid 44 depresses the plunger 42 thereby opening and maintaining open the vent valve 40, so that normal atmospheric pressure now exists in the interior of the vent tube 11. Because the liquid 2 attempts to enter into the tube 11 according to the principle of communicating vessels, there will automatically develop in the vessel 1 above the upper level 48 of the liquid that is in the space la'- a subatmospheric pressure.

If for dispensing purposes the armature 9 is lifted as a result of energization of the coil 10, and the valve member 7 moves from the closure position of FIG. 6 to the retracted dispensing-position of FIG. 7,'the liquid contained in the lower end of the vent tube 11 will flow into the receptacle 1 and the same amount of liquid will be dispensed via the outlet 3. The replenishing quantity of air which enters the receptacle 1 in form of air bubbles (see FIG. 7) during such dispensing thus regulates by itself over a brief period of time the amount of liquid which is dispensed. After the initial dispensing of liquid from the container, the liquid will not again rise in the lower end of the vent tube 11, this being avoided due to the fact that the sub-atmospheric pressure develops in the space la and that atmospheric pressure exists in the vent tube 11. This means that in. the receptacle 1 and the tube 11 the respective liquid levels 48 and 48a will develop asillustrated in FIG. 7. In other words, the relative liquid levels shown in FIG. 6'will occur only prior to the first time liquid is dispensed after filling of the receptacle 1; from then on the condition shown in FIG. 7 will prevail. I

If as a result of dispensing of the liquid the level 48- in the receptacle 1 drops to the lower edge of the vent tube 11, then it is advantageous to effect automatic refilling by devices which form no part'of the present invention, or to provide at least for an indicating arrangement which is activated when the level drops to this extent and which indicates that refilling should now be carried out.

It is a very significant advantage of the present invention that the liquids being dispensed can have high viscosity, that is that they may have enough sugar content to have for instance 60-70 Brix. With such an amount of sugar the liquid is largely self-preserving. Furthermore, even after most of the contents of the receptacle have been dispensed, additional liquid can be introduced without any difficulties. Thus, the present invention not only assures that .the amount of liquid which is dispensed during each dispensing operation will always be identical, irrespective of whether the liquid level is at its upper permissible point or at its lower permissible point, but also the development of sub-atmospheric pressure iin the space la can be automatically assured (in the embodiment of FIGS. 4 7) in response to the occurrence of a dispensing incident.

In addition, the heretofore so objectionable drying effect, that is the surface drying of the liquid at the upper level oron the walls bounding the space 1a, is

avoided with the present invention so that only infrequent cleaning of the receptacle 1 is required. This infrequent cleaning issufficient because the high sugar content of the liquid prevents bacteriological spoiling of the contents, and because no encrustations will form, especially because moisture cannot be yielded to the ambient atmosphere and the atmosphere in the space 1a will always be maintained at a sufficient level of humidity to prevent such drying.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the types described above.

While the invention has been illustrated and described as embodied in the dispensing of high-viscosity liquids, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the followingclaims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims: 1. An apparatus for dispensing viscous high sugarcontent liquids which tend to form incrustations unless exposed to an ambient atmosphere having relatively high moisture-content, comprising a receptacle defining a confining space for a supply of liquid and having a lower portion provided with an outlet opening; a valve for normally sealing said outlet opening; actuating means for operating said valve; a partition provided in said receptacle to separate a first portion of the surface of said supply of liquid from a second portion of said surface while permitting the liquid below said first portion to communicate with the liquid below said second portion at a level below said surface portions; and control means for continuously maintaining above said second surface portion one body of a gaseous medium at a pressure exceeding the pressure of another body of a gaseous medium above said first surface portion as long as the liquid below said first surface portion extends above said level whereby the opening of said valve results in discharge of a portion of said supply of liquid and in penetration of bubbles of said one body of gaseous medium through said second surface portion and subsequent rise of said bubbles toward said first surface portion with attendant increase in the moisture content of said bubbles, whereby the moisture content of said other body of gaseous medium increases as a result of the addition of the moisture content of said bubbles thereto upon penetration of said bubbles through said first surface portion, so as to prevent formation of incrustations in said receptacle by maintaining the moisture content of said other body of gaseous medium relatively high.

2. An apparatus as defined in claim 1, wherein said actuating means comprises a rod having a lower portion operatively connected with said valve and an upper portion located above said second surface portion of said supply of liquid, and electromagnetic means for shifting said rod lengthwise and for thereby effecting said opening of said valve;

3. An apparatus as defined in claim 2, wherein said electromagnetic means comprises an armature rigidly connected to said rod, and a stationary coil surrounding said armature and being energizable to shift said rod by way of said armature. I

4. An apparatus as defined in claim 2, wherein said electromagnetic means are located at least substantially outside said receptacle.

5. An apparatus as defined in claim 3; wherein said partition comprises a vent tube surrounding said rod over substantially the length thereof and including a free end portion located exteriorly of said receptacle and surrounding said armature; and wherein said coil surrounds said free end portion. I

6. An apparatus as defined in claim 2; wherein said partition comprises avent tube surrounding said rod over substantially the length thereof and having a bottom end portion in said lower portion of said receptacle, and a top end portion.

7. An apparatus as defined in claim 6; further comprising guide means carried by said bottom end portion of said vent tube for shiftably guiding said rod.

8. An apparatus as defined in claim 6; further comprising guide means carried by said bottom end portion of said vent tube for shiftably guiding said rod, and for preventing the same from movements leading to contact of said valve with said receptacle when said valve is in said open position thereof.

9. An apparatus as defined in claim 1, wherein said valve is of ball-shaped configuration.

10. An apparatus as defined in claim 1, wherein said valve is of at least part-conical configuration.

11. An apparatusas defined in claim 2; and further comprising the turnable attachment of means mounting said valve to said rod.

12. An apparatus as defined in claim 6, said receptacle having a bottom wall provided with said outlet opening said bottom end portion of said vent tube being open and beinglocated above said bottom wall.

13. An apparatus as defined in claim 6; wherein said control means comprises a vent valve provided at said top end portion of said vent tube and controlling communication of the latter with the ambient atmosphere surrounding said receptacle.

14. An apparatus as defined in claim 13, wherein said vent valve is normally closed and operative to open in response to the presence of sub-atmospheric pressure in said vent tube.

15. An apparatus as defined in claim 13', and further comprising control means for moving said vent valve to.

open position.

16. An apparatus as defined in claim 15, said receptacle having an inlet and, comprising cover means movable to and from a cover position covering said inlet; and wherein said control means is a part of said cover means.

17. An apparatus as defined in claim 16, said apparatus comprising a housing surrounding said receptacle, and said cover means including a lid of said housing; and wherein said control means is a portion of said lid which engages said vent valve and moves the same to open position when said lid is in said cover position.

18. An apparatus as defined in claim 1, said receptacle having an upper portion provided with an inlet; and

further comprising removable closure means for gasfaces said outlet opening. 

1. An apparatus for dispensing viscous high sugar-content liquids which tend to form incrustations unless exposed to an ambient atmosphere having relatively high moisture content, comprising a receptacle defining a confining space for a supply of liquid and having a lower portion provided with an outlet opening; a valve for normally sealing said outlet opening; actuating means for operating said valve; a partition provided in said receptacle to separate a first portion of the surface of said supply of liquid from a second portion of said surface while permitting the liquid below said first portion to communicate with the liquid below said second portion at a level below said surface portions; and control means for continuously maintaining above said second surface portion one body of a gaseous medium at a pressure exceeding the pressure of another body of a gaseous medium above said first surface portion as long as the liquid below said first surface portion extends above said level whereby the opening of said valve results in discharge of a portion of said supply of liquid and in penetration of bubbles of said one body of gaseous medium through said second surface portion and subsequent rise of said bubbles toward said first surface portion with attendant increase in the moisture content of said bubbles, whereby the moisture content of said other body of gaseous medium increases as a result of the addition of the moisture content of said bubbles thereto upon penetration of said bubbles through said first surface portion, so as to prevent formation of incrustations in said receptacle by maintaining the moisture content of said other body of gaseous medium relatively high.
 2. An apparatus as defined in claim 1, wherein said actuating means comprises a rod having a lower portion operatively connected with said valve and an upper portion located above said second surface portion of said supply of liquid, and electromagnetic means for shifting said rod lengthwIse and for thereby effecting said opening of said valve.
 3. An apparatus as defined in claim 2, wherein said electromagnetic means comprises an armature rigidly connected to said rod, and a stationary coil surrounding said armature and being energizable to shift said rod by way of said armature.
 4. An apparatus as defined in claim 2, wherein said electromagnetic means are located at least substantially outside said receptacle.
 5. An apparatus as defined in claim 3; wherein said partition comprises a vent tube surrounding said rod over substantially the length thereof and including a free end portion located exteriorly of said receptacle and surrounding said armature; and wherein said coil surrounds said free end portion.
 6. An apparatus as defined in claim 2; wherein said partition comprises a vent tube surrounding said rod over substantially the length thereof and having a bottom end portion in said lower portion of said receptacle, and a top end portion.
 7. An apparatus as defined in claim 6; further comprising guide means carried by said bottom end portion of said vent tube for shiftably guiding said rod.
 8. An apparatus as defined in claim 6; further comprising guide means carried by said bottom end portion of said vent tube for shiftably guiding said rod, and for preventing the same from movements leading to contact of said valve with said receptacle when said valve is in said open position thereof.
 9. An apparatus as defined in claim 1, wherein said valve is of ball-shaped configuration.
 10. An apparatus as defined in claim 1, wherein said valve is of at least part-conical configuration.
 11. An apparatus as defined in claim 2; and further comprising the turnable attachment of means mounting said valve to said rod.
 12. An apparatus as defined in claim 6, said receptacle having a bottom wall provided with said outlet opening said bottom end portion of said vent tube being open and being located above said bottom wall.
 13. An apparatus as defined in claim 6; wherein said control means comprises a vent valve provided at said top end portion of said vent tube and controlling communication of the latter with the ambient atmosphere surrounding said receptacle.
 14. An apparatus as defined in claim 13, wherein said vent valve is normally closed and operative to open in response to the presence of sub-atmospheric pressure in said vent tube.
 15. An apparatus as defined in claim 13; and further comprising control means for moving said vent valve to open position.
 16. An apparatus as defined in claim 15, said receptacle having an inlet and, comprising cover means movable to and from a cover position covering said inlet; and wherein said control means is a part of said cover means.
 17. An apparatus as defined in claim 16, said apparatus comprising a housing surrounding said receptacle, and said cover means including a lid of said housing; and wherein said control means is a portion of said lid which engages said vent valve and moves the same to open position when said lid is in said cover position.
 18. An apparatus as defined in claim 1, said receptacle having an upper portion provided with an inlet; and further comprising removable closure means for gas-tightly closing said inlet.
 19. An apparatus as defined in claim 6, wherein said vent tube is inclined with respect to a horizontal plane, and wherein said bottom end portion of said vent tube faces said outlet opening. 